The Daniel Defense Castle Nut will secure your mil spec or commercial spec carbine receiver extension and rear receiver end plate to the lower receiver. Made with recesses for staking your rear receiver end plate to prevent the castle nut from coming loose. It is finished with a heavy magnesium phosphate coating and is compatible with common armorers/castle nut wrenches (not included).
All Daniel Defense products carry a 100% satisfaction guarantee against defects in original materials and workmanship. If your Daniel Defense product shows evidence of such defects, Daniel Defense will make every accommodation to fix, repair, or replace your product in the most expeditious manner possible. Daniel Defense does not warranty products or damage caused to our products by the correct or incorrect installation of other manufacturer's products.